An unethical Politician for trying to sway the general public to vote for him/her.
Second the uneducated voter who takes him/her for their word and doesn’t check the facts and figures or even the background behavior.

The bad voter doesn’t figure into the equation. What they do is neither here nor there, but the bad politician is EVERYWHERE by comparison.

The bad politician.

If you only had good politicians, bad voters would at worst choose a good politician randomly or not the best of the good politicians.

Truly bad voters tend to be a product of bad politicians and bad political parties and the other groups that foster them and promote them to the voters.

There’s never a field of decent politicians and then a mass of bad voters shows up and starts somehow organizing by themselves to vote in someone terrible.

First the snake oil salesman rolls in to town and sets up his stall then he tells you how his beautiful potion can cure almost anything and finally the good citizens go into a frenzy to buy the stuff before it runs out.